The revision of the Company Law in 2018 has spurred the rapid development of share repurchases among A-share listed companies in China. However, existing research, both domestically and internationally, has yet to find evidence that repurchases in China create long-term value for shareholders, instead only demonstrating short-term market reactions. Stimulated by these short-term effects, share repurchases may potentially harm stakeholders by triggering opportunistic behaviors. Therefore, understanding the economic consequences of share repurchases, deciphering their mechanisms, clarifying applicable scenarios, and subsequently employing this financial tool reasonably are of significant theoretical and practical relevance.

This paper examines A-share listed companies included in the margin trading and short selling (MTSS) program from 2010 to 2021, using the period from the repurchase announcement date to the completion date as an interval shock. By constructing a PSM-DID model, it tests the causal relationship between share repurchases and short-selling pressure. The results indicate that: (1) After the completion of repurchases, short-selling pressure on target companies significantly increases compared to the pre-announcement period. This suggests that share repurchases do not necessarily convey “good news”, as traders seek to hedge against future price risks, thereby increasing short-selling pressure. (2) A phased analysis reveals that the market’s short-selling behavior in response to share repurchases primarily emerged after the 2018 revision of the Company Law, indicating that the policy relaxation on repurchases did not fully achieve the goal of preserving market value. Instead, the potential risks of repurchasing companies were captured by forward-looking traders. (3) Heterogeneity analysis at the firm level shows that companies with excessive debt, high financial distress, and significant financing constraints bear greater short-selling pressure after repurchases.

The potential contributions of this paper are as follows: First, it emphasizes that share repurchases, as a financial instrument, do not inherently possess positive or negative attributes; their outcomes vary under diffe- rent conditions. This provides a theoretical basis for the reasonable and moderate use of this tool. Second, it reveals investors’ reactions to share repurchases, offering supplementary empirical evidence on the impact of short-selling mechanisms on pricing efficiency. Third, it addresses market noise caused by technical operations during the repurchase execution period by constructing an interval shock model. Fourth, it characterizes the potential long-term risks in share repurchases from the perspective of MTSS transactions, identifying possible risk spillover effects. This provides insights for policymakers to implement necessary and appropriate regulatory measures following the relaxation of repurchase policies.